Measurement of theP13lifetime in Sr

Measurement of the cross sections for collisional broadening of the intercombination transitions in calcium and strontium

“…These velocities along with the interaction coeScients give a(Sr-Ne) =9. 12 (f =1.0X10 [16]) interaction agree reasonably well.…”

“…5. The lifetime of the 5s 'S0~5s5p P, transition in strontium is 22 ps [16], which corresponds to a linewidth of 7.23 kHz. This value is smaller than the error bar in our measurement, and consequently less than the accuracy of this technique.…”

“…For the case of foreign gas broadening, the spectral broadening cross section is given by [24] 0 =2m f [1cosy(p)]pdp, (13) where ri(p) is the phase change of the classical radiating oscillator caused by a collision which occurs at an impact parameter p. The phase change is defined as ri(p) =f V(R)dt, (14) where V(R) is the interaction potential and the interaction distance R is assumed to be R =p -(vr ) (15) corresponding to a straight line trajectory for the perturbing atom. Transforming phase change into an integral involving distance, we have 1~V(R)R dR ri(p) =-[R 2 2]1/2 (16) For broadening by a foreign gas, we will assume that the interaction between the atoms is described by the Lennard-Jones [25] potential: For the foreign gas interactions involving Sr, we have been unable to find published theoretical or experimental values of C6 and C,2. We can, however, approximate these using the corresponding calcium parameters and simple scaling assumptions.…”

Radiative lifetimes of the lowest 3P1 metastable states of Ca and Sr

“…The mean radiative lifetimes for Ca( 3 P 1 ) and Sr( 3 P 1 ) have been investigated by a variety of experimental methods, including interferometric measurements [1,2], atomic beam techniques [3][4][5][6] and time-resolved either emission or absorption studies following dye laser excitation [7][8][9][10][11][12][13][14][15] as well as being the object of theoretical calculations [6][7][8][9][10][11][12][13][14][15][16][17][18][19]. The optically metastable excited states of these atoms have been studied especially with regards to processes leading to the observation of chemiluminescence.…”

Some Investigations of the Chemiluminescence Spectra from the Reactions of Ca and Sr with SF6

“…But by the reaction (4) these molecules can in a secondary reaction produce metastable M atoms by v -e-transfer. These atoms have a comparably long life time (r 10~5 s according to [16,17]) and can therefore be suggested to be responsible for the reaction (5). To confirm this suggestion the inten sity of the molecular bands and that of the metas table Ca-line were measured as a function of the SFö pressure in the chamber [18].…”